World number one Rory McIlroy had an unexpected traffic jam as well as a somewhat erratic game to deal with as he began the defence of his BMW PGA Championship title on Thursday.

McIlroy was among the early starters at Wentworth as he looked to claim a third win in four events, having followed his victory in the WGC-Cadillac Match Play with a third consecutive top-10 finish in the Players Championship and a seven-shot triumph at Quail Hollow on Sunday.

Playing alongside Ryder Cup team-mates Jamie Donaldson and Martin Kaymer, McIlroy got off to a poor start with a bogey on the first, failing to find the green with his approach and missing from 12 feet for par after a poor chip.

To the delight of the large crowds, the 26-year-old quickly made amends with a birdie from 15 feet on the second, before having to wait on the third tee as a number of cars crossed the fairway to reach one of the spectator car parks.

A birdie on the par-five fourth got McIlroy into red figures, but he promptly gave the shot back with a bogey on the fifth and had to wait until the 12th for his next birdie, courtesy of a superb pitch over a greenside bunker.

Once again McIlroy immediately dropped a shot on the next, but an excellent tee shot to six feet on the 14th - where Miguel Angel Jimenez was six inches short of winning a BMW i8 for a hole-in-one - got the Northern Irishman back to one under.

That was three shots off the clubhouse lead shared by England's Chris Wood and Spanish pair Jimenez and Jorge Campillo, with their compatriot Pablo Larrazabal a shot behind after a 69.

Wood has played just six events this season after spending five months on the sidelines with a broken bone in his wrist, suffered during a tennis lesson in October.

"It's a long way for me to fall and it hurt," joked the 6ft 6in Bristolian. "I was in a cast for two months and it was a nightmare to miss out on the desert swing this year - particularly as I won in Qatar in 2013 - watching on telly when it's freezing at home and 30 degrees in Dubai.

"It's been a struggle and feels like I have been working hard to finish 30th every week. I did finish third in Morocco but I think it was always going to be a bit of a battle after five months.

"But we are coming into the meat of the season now so hopefully I can find my form."

Wood carded five birdies in his first 14 holes and looked set to take advantage of the closing par fives, but pulled his second shot on the 17th out of bounds and missed from close range on the 18th.

"It's disappointing to finish six, five but the second shot on the 17th was the only poor one I hit all day," he added. "I've been fighting a left shot for a year now."

Scotland's Stephen Gallacher had been forced to withdraw from the event before play began due to a wrist injury, with his replacement Robert Dinwiddie perhaps unsurprisingly starting his round just 30 minutes later with a double bogey on the first.